Improvement in printing-telegraphs



T. A. Emsou.

Printing Telegraphs. NO. 139,129. Patent ed May 20.1873.

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UNITED STATES PATENT OFFICE.

THOMAS A. EDISON, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE GOLD AND STOCK TELEGRAPH COMPANY, NEW YORK, N. Y.-

IMPROVEMENT IN PRlNTlNG-TELEGRAPHS.

Specification forming part of Letters Patent No. 139, 129 dated May 20, 1873 application filed February 18, 1873.

To all whom it may concern:

Be it known that 1, THOMAS A. EDISON, of Newark, in the county of Essex and State of New Jersey, have invented an Improvement in Transmitting-Instruments for Printing-Telegraphs, of which the following is a specification In this instrument there are two electromagnets in a main-line circuit, in which, also, is the key or other instrument for opening and closing the circuit. .The relay-magnets are provided with armatures and circuitclosers, and the retractile springs of the armatures are of different tensions, so that the relay, working a local circuit through the typewheel magnet of the printing-instrument, energizes the same each pulsation in the main line. The local circuit of the printing-magnet remains broken, because the armature of that relay-magnet is kept toward the magnet by the residual magnetism until a pause in the transmission occurs sufficient to allow the printing relay-armature to recede and close the relay circuit to the printing-magnets. In this manner it is only necessary topulsate the main-line circuit and pause to efi'ect the printing when the type-wheel has been set.

In the drawing, Figure 1 shows a printingtelegraph instrument of any desired character, a representing the type-wheel magnet, and bthe printing-magnet. Fig. 2 is a plan of the relay-instrument.

The magnets d and e are in the mainline circuit from the battery f, and g is a finger-key or other closer at the distant stawheel magnet a in the various printing-in: struments; thereby the type-wheels will be set by such pulsations. During these pulsa tions the armature 2' will be held toward the electro-magnet 6, because of the residual magnetisin and slight tension of the retractile spring of the armature; but when a pause occurs the magnet e discharges itself, the armature i is drawn away, and the relay cir cuit l closed to the printing-magnets b, so as to give the impression. If the printing is to be elfected when the local circuit 70 is closed, the connection will be made to the screw 3 instead of the screw 2. WVith circuits arranged as in the diagram, Fig. 3, only one local battery will be required, the connections and operations corresponding with those before described. The magnet d may be used for setting the typ( -wheel by direct action of the armature on pallets, and the armature of the magnet e be used to close the local circuit to the printing-magnet b, as before.

I claim as my invention- 1. Two relay-magnets in the main circuit, with retractile springs to the armatures of different tensions, in combination with relay circuits to the type-wheel and printing electromagnets, respectively, of a printing-telegraph instrument, substantially as and for the purposes set forth. 7

2. Two relay-magnets in the main circuit, with armatures adjusted differently, in combination with a local circuit effecting distinct and different operations, according to the length of pause between pulsations in the main line, substantially as specified.

Signed this 13th day of February, AD. 1873.

THOMAS A. EDISON.

Witnesses:

GEo. T. PINCKNEY, CHAS. E. SMITH. 

